The common starling (Sturnus vulgaris), also known as the European starling, or in the British Isles just the starling, is a medium-sized passerine bird in the starling family, Sturnidae. It is about 20 cm (8 in) long and has glossy black plumage with a metallic sheen, which is speckled with white at some times of year. The legs are pink and the bill is black in winter and yellow in summer; young birds have browner plumage than the adults. It is a noisy bird, especially in communal roosts and other gregarious situations, with an unmusical but varied song. Its gift for mimicry has been noted in literature including the Mabinogion and the works of Pliny the Elder and William Shakespeare.
The common starling has about a dozen subspecies breeding in open habitats across its native range in temperate Europe and western Asia, and it has been introduced to Australia, New Zealand, Canada, United States, Mexico, Peru, Argentina, the Falkland Islands, Brazil, Chile, Uruguay, South Africa and Fiji.[2] This bird is resident in southern and western Europe and southwestern Asia, while northeastern populations migrate south and west in winter within the breeding range and also further south to Iberia and North Africa. The common starling builds an untidy nest in a natural or artificial cavity in which four or five glossy, pale blue eggs are laid. These take two weeks to hatch and the young remain in the nest for another three weeks. There are normally one or two breeding attempts each year. This species is omnivorous, taking a wide range of invertebrates, as well as seeds and fruit. It is hunted by various mammals and birds of prey, and is host to a range of external and internal parasites.
Large flocks typical of this species can be beneficial to agriculture by controlling invertebrate pests; however, starlings can also be pests themselves when they feed on fruit and sprouting crops. Common starlings may also be a nuisance through the noise and mess caused by their large urban roosts. Introduced populations in particular have been subjected to a range of controls, including culling, but these have had limited success except in preventing the colonisation of Western Australia. The species has declined in numbers in parts of northern and western Europe since the 1980s due to fewer grassland invertebrates being available as food for growing chicks. Despite this, its huge global population is not thought to be declining significantly, so the common starling is classified as being of least concern by the International Union for Conservation of Nature.
Taxonomy and systematics[edit]
The common starling was first described by Linnaeus in his Systema Naturae in 1758 under its current binomial name.[3] Sturnus and vulgaris are derived from the Latin for "starling" and "common" respectively.[4]The Old English staer, later stare, and the Latin sturnus are both derived from an unknown Indo-European root dating back to the second millennium BC. "Starling" was first recorded in the 11th century, when it referred to the juvenile of the species, but by the 16th century it had already largely supplanted "stare" to refer to birds of all ages.[5] The older name is referenced in William Butler Yeats' poem "The Stare's Nest by My Window".[6] The International Ornithological Congress' preferred English vernacular name is common starling.[7]
The starling family, Sturnidae, is an entirely Old World group apart from introductions elsewhere, with the greatest numbers of species in Southeast Asia and sub-Saharan Africa.[8] The genus Sturnus is polyphyletic and relationships between its members are not fully resolved. The closest relation of the common starling is the spotless starling.[9] The non-migratory spotless starling may be descended from a population of ancestral S. vulgaris that survived in an Iberian refugium during an ice age retreat,[10] and mitochondrial gene studies suggest that it could be considered as a subspecies of the common starling. There is more genetic variation between common starling populations than between nominate common starling and spotless starling.[11] Although common starling remains are known from the Middle Pleistocene,[12] part of the problem in resolving relationships in the Sturnidae is the paucity of the fossil record for the family as a whole.[10]
Subspecies[edit]
There are several subspecies of the common starling, which vary clinally in size and the colour tone of the adult plumage. The gradual variation over geographic range and extensive intergradation means that acceptance of the various subspecies varies between authorities.[13][14]
- Subspecies
| Subspecies | Authority | Range | Comments |
|---|---|---|---|
| S. v. vulgaris | Linnaeus, 1758 | Most of Europe, except the far northwest and far southeast; also Iceland and the Canary Islands | The nominate subspecies. |
| S. v. faroensis | Feilden, 1872 | Faroe Islands | Slightly larger than nominate, especially bill and feet. Adult with darker and duller green gloss and far less spotting even in fresh plumage. Juvenile sooty black with whitish chin and areas on belly; throat spotted black. |
| S. v. zetlandicus | Hartert, 1918. | Shetland Islands | Like faroensis but intermediate in size between that and vulgaris. Birds from Fair Isle, St Kilda and the Outer Hebrides are intermediate between this subspecies and the nominate and placement with vulgaris or zetlandicus varies according to authority. |
| S. v. granti | Hartert, 1903 | Azores | Like nominate, but smaller, especially feet. Often strong purple gloss on upperparts. |
| S. v. poltaratskyi | (Finsch, 1878) | Eastern Bashkortostan eastwards through Urals and central Siberia, to Lake Baykal and western Mongolia | Like nominate, but gloss on head predominantly purple, on back green, on flanks usually purplish-blue, on upper wing-coverts bluish-green. In flight, conspicuous light cinnamon-buff fringes to under wing-coverts and axillaries; these areas may appear very pale in fresh plumage. |
| S. v. tauricus | Buturlin, 1904 | From Crimea and E of Dnieper River eastwards around coast of Black Sea to W Asia Minor. Not in uplands where replaced by purpurascens | Like nominate, but decidedly long-winged. Gloss of head green, of body bronze-purple, of flanks and upper wing-coverts greenish bronze. Underwing blackish with pale fringes of coverts. Nearly spotless in breeding plumage. |
| S. v. purpurascens | Gould, 1868 | E Turkey to Tbilisi and Lake Sevan, in uplands on E shore of Black Sea replacing tauricus | Like nominate, but wing longer and green gloss restricted to ear-coverts, neck and upper chest. Purple gloss elsewhere except on flanks and upper wing-coverts where more bronzy. Dark underwing with slim white fringes to coverts. |
| S. v. caucasicus | Lorenz, 1887 | Volga Delta through eastern Caucasus and adjacent areas | Green gloss on head and back, purple gloss on neck and belly, more bluish on upper wing-coverts. Underwing like purpurascens. |
| S. v. porphyronotus | (Sharpe, 1888) | Western Central Asia, grading into poltaratskyi between Dzungarian Alatau and Altai | Very similar to tauricus but smaller and completely allopatric, being separated by purpurascens, caucasicus and nobilior. |
| S. v. nobilior | (Hume, 1879) | Afghanistan, SE Turkmenistan and adjacent Uzbekistan to E Iran | Like purpurascens but smaller and wing shorter; ear-coverts glossed purple, and underside and upperwing gloss quite reddish. |
| S. v. humii | (Brooks, 1876) | Kashmir to Nepal | Small; purple gloss restricted to neck area and sometimes flanks to tail-coverts, otherwise glossed green. This is sometimes treated under the name indicus given by Hodgson.[b] |
| S. v. minor | (Hume, 1873) | Pakistan | Small; green gloss restricted to head and lower belly and back, otherwise glossed purple. |
Birds from Fair Isle, St Kilda and the Outer Hebrides are intermediate in size between S. v. zetlandicus and the nominate form, and their subspecies placement varies according to the authority. The dark juveniles typical of these island forms are occasionally found in mainland Scotland and elsewhere, indicating some gene flow from faroensis or zetlandicus, subspecies formerly considered to be isolated.[18][19]
Several other subspecies have been named, but are generally no longer considered valid. Most are intergrades that occur where the ranges of various subspecies meet. These include: S. v. ruthenus Menzbier, 1891 and S. v. jitkowi Buturlin, 1904, which are intergrades between vulgaris and poltaratskyi from western Russia; S. v. graecus Tschusi, 1905 and S. v. balcanicus Buturlin and Harms, 1909, intergrades between vulgaris and tauricus from the southern Balkans to central Ukraine and throughout Greece to the Bosporus; and S. v. heinrichi Stresemann, 1928, an intergrade between caucasicus and nobilior in northern Iran. S. v. persepolis Ticehurst, 1928 from southern Iran's (Fars Province) is very similar to S. v. vulgaris, and it is not clear whether it is a distinct resident population or simply migrants from southeastern Europe.[14]
Description[edit]
The common starling is 19–23 cm (7.5–9.1 in) long, with a wingspan of 31–44 cm (12–17 in) and a weight of 58–101 g (2.0–3.6 oz).[15] Among standard measurements, the wing chord is 11.8 to 13.8 cm (4.6 to 5.4 in), the tail is 5.8 to 6.8 cm (2.3 to 2.7 in), the culmen is 2.5 to 3.2 cm (0.98 to 1.26 in) and the tarsus is 2.7 to 3.2 cm (1.1 to 1.3 in).[15]The plumage is iridescent black, glossed purple or green, and spangled with white, especially in winter. The underparts of adult male common starlings are less spotted than those of adult females at a given time of year. The throat feathers of males are long and loose and are used in display while those of females are smaller and more pointed. The legs are stout and pinkish- or greyish-red. The bill is narrow and conical with a sharp tip; in the winter it is brownish-black but in summer, females have lemon yellow beaks while males have yellow bills with blue-grey bases. Moulting occurs once a year- in late summer after the breeding season has finished; the fresh feathers are prominently tipped white (breast feathers) or buff (wing and back feathers), which gives the bird a speckled appearance. The reduction in the spotting in the breeding season is achieved through the white feather tips largely wearing off. Juveniles are grey-brown and by their first winter resemble adults though often retaining some brown juvenile feathering, especially on the head.[13][20] They can usually be sexed by the colour of the irises, rich brown in males, mouse-brown or grey in females. Estimating the contrast between an iris and the central always-dark pupil is 97% accurate in determining sex, rising to 98% if the length of the throat feathers is also considered.[21][22] The common starling is mid-sized by both starling standards and passerine standards. It is readily distinguished from other mid-sized passerines, such as thrushes, icterids or small corvids, by its relatively short tail, sharp, blade-like bill, round-bellied shape and strong, sizeable (and rufous-coloured) legs. In flight, its strongly pointed wings and dark colouration are distinctive, while on the ground its strange, somewhat waddling gait is also characteristic. The colouring and build usually distinguish this bird from other starlings, although the closely related spotless starling may be physically distinguished by the lack of iridescent spots in adult breeding plumage.[23]
Like most terrestrial starlings the common starling moves by walking or running, rather than hopping. Their flight is quite strong and direct; their triangular-shaped wings beat very rapidly, and periodically the birds glide for a short way without losing much height before resuming powered flight. When in a flock, the birds take off almost simultaneously, wheel and turn in unison, form a compact mass or trail off into a wispy stream, bunch up again and land in a coordinated fashion.[20] Common starling on migration can fly at 60–80 km/h (37–50 mph) and cover up to 1,000–1,500 km (620–930 mi).[24]
Several terrestrial starlings, including those in the genus Sturnus, have adaptations of the skull and muscles that help with feeding by probing.[25] This adaptation is most strongly developed in the common starling (along with the spotless and white-cheeked starlings), where the protractor muscles responsible for opening the jaw are enlarged and the skull is narrow, allowing the eye to be moved forward to peer down the length of the bill.[26] This technique involves inserting the bill into the ground and opening it as a way of searching for hidden food items. Common starlings have the physical traits that enable them to use this feeding technique, which has undoubtedly helped the species spread far and wide.[15]
In Iberia, the western Mediterranean and northwest Africa, the common starling may be confused with the closely related spotless starling, the plumage of which, as its name implies, has a more uniform colour. At close range it can be seen that the latter has longer throat feathers, a fact particularly noticeable when it sings.[27]
Voice[edit]
The common starling is a noisy bird. Its song consists of a wide variety of both melodic and mechanical-sounding noises as part of a ritual succession of sounds. The male is the main songster and engages in bouts of song lasting for a minute or more. Each of these typically includes four varieties of song type, which follow each other in a regular order without pause. The bout starts with a series of pure-tone whistles and these are followed by the main part of the song, a number of variable sequences that often incorporate snatches of song mimicked from other species of bird and various naturally occurring or man-made noises. The structure and simplicity of the sound mimicked is of greater importance than the frequency with which it occurs. Each sound clip is repeated several times before the bird moves on to the next. After this variable section comes a number of types of repeated clicks followed by a final burst of high-frequency song, again formed of several types. Each bird has its own repertoire with more proficient birds having a range of up to 35 variable song types and as many as 14 types of clicks.[28]
Males sing constantly as the breeding period approaches and perform less often once pairs have bonded. In the presence of a female, a male sometimes flies to his nest and sings from the entrance, apparently attempting to entice the female in. Older birds tend to have a wider repertoire than younger ones. Those males that engage in longer bouts of singing and that have wider repertoires attract mates earlier and have greater reproductive success than others. Females appear to prefer mates with more complex songs, perhaps because this indicates greater experience or longevity. Having a complex song is also useful in defending a territory and deterring less experienced males from encroaching.[28]
Singing also occurs outside the breeding season, taking place throughout the year apart from the moulting period. The songsters are more commonly male although females also sing on occasion. The function of such out-of-season song is poorly understood.[28] Eleven other types of call have been described including a flock call, threat call, attack call, snarl call and copulation call.[29] The alarm call is a harsh scream, and while foraging together common starlings squabble incessantly.[20] They chatter while roosting and bathing, making a great deal of noise that can cause irritation to people living nearby. When a flock of common starlings is flying together, the synchronised movements of the birds' wings make a distinctive whooshing sound that can be heard hundreds of metres (yards) away.
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